max5883egmtd Maxim Integrated Products, Inc., max5883egmtd Datasheet - Page 11

• Manufacturer Part Number: max5883egmtd
• Description: Max5883 3.3v, 12-bit, 200msps High Dynamic Performance Dac With Cmos Inputs
• Manufacturer: Maxim Integrated Products, Inc.

The MAX5883 also features an active-high power-down
mode, which allows the user to cut the DAC’s current
consumption. A single pin (PD) is used to control the
power-down mode (PD = 1) or reactivate the DAC (PD
= 0) after power-down.
Enabling the power-down mode of this 12-bit CMOS
DAC allows the overall power consumption to be
reduced to less than 1mW. The MAX5883 requires
10ms to wake up from power-down and enter a fully
operational state.
The differential voltage existing between IOUTP and
IOUTN can also be converted to a single-ended volt-
age using a transformer (Figure 6) or a differential
amplifier configuration. Using a differential transformer-
coupled output, in which the output power is limited to
0dBm, can optimize the dynamic performance.
However, make sure to pay close attention to the trans-
former core saturation characteristics when selecting a
transformer for the MAX5883. Transformer core satura-
tion can introduce strong 2nd-harmonic distortion,
especially at low output frequencies and high signal
amplitudes. It is also recommended to center tap the
transformer to ground. If no transformer is used, each
DAC output should be terminated to ground with a 50
Figure 5. Detailed Timing Relationship
B0 TO B15
CLKN
CLKP
IOUT
Applications Information
N - 5
Differential Coupling Using a
______________________________________________________________________________________
DIGITAL DATA IS LATCHED ON
THE RISING EDGE OF CLKP
t SETUP
Wideband RF Transformer
Power-Down Operation (PD)
Performance DAC with CMOS Inputs
N - 1
3.3V, 12-Bit, 200Msps High Dynamic
t HOLD
N - 4
OUTPUT DATA IS UPDATED ON
THE FALLING EDGE OF CLKP
t PD
N
N - 3
resistor. Additionally, a 100
between the outputs.
If a single-ended unipolar output is desirable, IOUTP
should be selected as the output, with IOUTN ground-
ed. However, driving the MAX5883 single ended is not
recommended since additional noise is added (from
the ground plane) in such configurations.
The distortion performance of the DAC depends on the
load impedance. The MAX5883 is optimized for a 50
double termination. It can be used with a transformer
output as shown in Figure 7 or just one 50
from each output to ground and one 50
between the outputs. This produces a full-scale output
power of up to 0dBm, depending on the output current
setting. Higher termination impedance can be used at
the cost of degraded distortion performance and
increased output noise voltage.
The transmitter sections of BTS applications serving
CDMA and W-CDMA architectures must generate carri-
ers with minimal coupling of carrier energy into the adja-
cent channels. A transmit mask (Tx mask) exists for this
application. The spread-spectrum modulation function
applied to the carrier frequency generates a spectral
response, which is uniform over a given bandwidth (up
to 4MHz) for a W-CDMA-modulated carrier.
Adjacent Channel Leakage Power Ratio
N + 1
(ACLR) Testing for CDMA- and
W-CDMA-Based Base Station
N - 2
Transceiver Systems (BTS)
t CH
resistor should be placed
t CL
N + 2
N - 1
resistor
resistor
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